Prevent connection errors from messing up /servers response

See bobthecow#46

CHANGELOG.markdown

@@ -1,3 +1,8 @@
+## v2.1.5
+
+ * Prevent connection errors from messing up `/servers` response (Ruby backend) — See #46
+
+
 ## v2.1.4
 
  * Add warning messages for `magic_quotes_gpc` and `magic_quotes_runtime` — See #49.

genghis.rb

@@ -474,6 +474,8 @@ def to_json(*)
 
       def connection
         @connection ||= Mongo::Connection.from_uri(@dsn, :connect_timeout => 1)
+      rescue StandardError => e
+        raise Mongo::ConnectionFailure.new(e.message)
       end
 
       def info

src/rb/genghis/models/server.rb

@@ -82,6 +82,8 @@ def to_json(*)
 
       def connection
         @connection ||= Mongo::Connection.from_uri(@dsn, :connect_timeout => 1)
+      rescue StandardError => e
+        raise Mongo::ConnectionFailure.new(e.message)
       end
 
       def info